摘要:
A tunable narrow linewidth laser is provided, wherein an adjustable etalon structure is employed to simultaneously tune the wavelength of the laser transmission and the length of the laser cavity. The etalon structure is an effective, relatively thick shear plate comprised of transparent matched wedge-shaped substrates and a pair of parallel, partially transmissive mirrors with a space therebetween. Rotation of the etalon structure relative to the laser input changes the angle of incidence to the first substrate and the etalon angle, thereby changing the wavelength of the laser light and also changing the length of the external laser cavity. Thus, reliable frequency tuning is achieved, without mode hopping.